Detección de novedad y codificación predictiva en el sistema auditivo: Impacto clínico en disfunciones auditivas y vestibulares. Revisión de la literatura / Deviance detection and predictive coding in the auditory system: Clinical impact in auditory and vestibular dysfunctions

Una propiedad fundamental de los sistemas sensoriales es su capacidad para detectar estímulos novedosos en el entorno. El sistema nervioso posee neuronas que disminuyen su respuesta a los estímulos sonoros que se repiten a lo largo del tiempo y otras neuronas que aumentan su frecuencia de disparo ante estímulos novedosos, siendo la diferencia entre ambas respuestas conocida como adaptación-específica a estímulos. En las últimas décadas, se ha propuesto que el cerebro establece, continuamente, predicciones de los estímulos novedosos y del entorno basándose en sus experiencias previas y en modelos de representación internos, teoría denominada codificación predictiva. En esta revisión, abordaremos algunos conceptos de la adaptación-específica a estímulos y codificación predictiva, centrándonos principalmente en el sistema auditivo. Por último, propondremos una explicación teórica basada en el marco de la codificación predictiva para algunas disfunciones neuropsiquiátricas, auditivas y vestibulares.

A fundamental property of sensory systems is their ability to detect novel stimuli in the environment. The nervous system possesses neurons that decrease their response to sound stimuli that are repeated over time and other neurons that increase their firing rate to novel stimuli, the difference between the two responses being known as stimulus-specific adaptation. In recent decades, it has been proposed that the brain continuously makes predictions of novel stimuli and the environment based on its previous experiences and internal representational models, a theory called predictive coding. In this review, we will address some concepts of stimulus-specific adaptation and predictive coding, focusing mainly on the auditory system. Finally, we will propose a theoretical explanation based on the predictive coding framework for some neuropsychiatric, auditory, and vestibular dysfunctions.

Implicit, But Not Explicit, Emotion Regulation Relieves Unpleasant Neural Responses Evoked by High-Intensity Negative Images / 神经科学通报·英文版

Evidence suggests that explicit reappraisal has limited regulatory effects on high-intensity emotions, mainly due to the depletion of cognitive resources occupied by the high-intensity emotional stimulus itself. The implicit form of reappraisal has proved to be resource-saving and therefore might be an ideal strategy to achieve the desired regulatory effect in high-intensity situations. In this study, we explored the regulatory effect of explicit and implicit reappraisal when participants encountered low- and high-intensity negative images. The subjective emotional rating indicated that both explicit and implicit reappraisal down-regulated negative experiences, irrespective of intensity. However, the amplitude of the parietal late positive potential (LPP; a neural index of experienced emotional intensity) showed that only implicit reappraisal had significant regulatory effects in the high-intensity context, though both explicit and implicit reappraisal successfully reduced the emotional neural responses elicited by low-intensity negative images. Meanwhile, implicit reappraisal led to a smaller frontal LPP amplitude (an index of cognitive cost) compared to explicit reappraisal, indicating that the implementation of implicit reappraisal consumes limited cognitive control resources. Furthermore, we found a prolonged effect of implicit emotion regulation introduced by training procedures. Taken together, these findings not only reveal that implicit reappraisal is suitable to relieve high-intensity negative experiences as well as neural responses, but also highlight the potential benefit of trained implicit regulation in clinical populations whose frontal control resources are limited.

Evaluation of Visual Acuity of Ametropia with Visual Event-Related Potential Nogo-P3 Component / 法医学杂志

OBJECTIVES@#To analyze the Nogo-P3 component of event-related potential (ERP) in the process of visual acuity processing, to provide electrophysiological evidence for objective evaluation of visual acuity.@*METHODS@#Twenty-six subjects with no other ocular diseases except for ametropia were recruited, and all subjects had uncorrected visual acuity both eyes 1/10 (evaluated using Monoyer chart). Block letter E with different visual angles and directions were used as graphic stimuli. The Go/Nogo paradigm was used for ERP studies. The visual angle of Go stimulation angle was 1°15', Nogo stimuli were 1°15', 55', 24' and 15'. The visual acuity test was performed on each of the two naked eyes separately in all subjects, and the characteristics of the Nogo-P3 component were analyzed.@*RESULTS@#The latency of Nogo-P3 showed no difference between the stimuli of 1°15' and 55', and between Nogo stimulation angle 24' and 15'. There was significant difference between Nogo stimulation angle 1°15' and 24', and between Nogo stimulation angle 1°15' and 15' (P<0.05). There was significant difference between Nogo stimulation angle 55' and 24', and between Nogo stimulation angle 55' and 15' (P<0.05). No significant differences were observed in the Nogo-P3 amplitude among Nogo stimulation.@*CONCLUSIONS@#In the Go/Nogo paradigm, Nogo-P3 can reflect the cognitive response of subjects to Nogo stimulation, which can be used for objective evaluation of visual acuity.

Forward masking with frequency-following response analyses

ABSTRACT Purpose: to analyze forward masking in normally hearing young people, by using frequency-following responses. Methods: the synthetic syllable /da/ was used for the recordings of ten individuals, in the following conditions: /da/ with no masking, and /da/ after 4, 16, 32, and 64 milliseconds of masking. F-test (ANOVA) was applied for repeated measures with the Greenhouse-Geisser correction to compare testing conditions. For significant differences, multiple comparisons (between pairs of conditions) and Bonferroni correction were used. Data normality was verified by applying the Shapiro-Wilk test, and statistical significance was used at 5%. Results: wave latencies of all masking conditions were compared with those of no masking. A latency delay was observed in the transient region of the response (PV and A) in all masking conditions, except for 64 milliseconds. Latency delay also occurred for waves PW, PX, and PY, which corresponded to the sustained region of the response. Conclusion: forward masking was observed, by using frequency-following responses with /da/ syllable in four intervals (4, 16, 32, and 64 ms) of preceding masking. Forward masking was more evident in the transient region of the response than in the sustained one. This study highlights the importance of electrophysiological testing in temporal processing assessment.

Tinnitus and event related potentials: a systematic review / Zumbido e potenciais evocados auditivos relacionados a eventos: uma revisão sistemática

Abstract Introduction Tinnitus is sound perception in the absence of a sound source. Changes in parameters of latency and amplitude on the auditory event related potentials or long latency potentials waves have been cited in tinnitus patients when compared to a control group. Objective To perform an assessment of scientific evidence that verifies the possibility of alterations in latency or amplitude of the waves of event related potentials in individuals with tinnitus. Methods By using SciELO, Lilacs, ISI Web and PubMed, scientific databases, a review was performed. Articles published in English, Portuguese, French and Spanish that correlated tinnitus with changes in event related potentials were included in this review. Results Twelve articles were located, however only eight fulfilled the criteria for inclusion. Conclusion The sample of selected studies demonstrate that the long latency auditory evoked potentials related to events between the control and tinnitus patients showed some changes in latency and or amplitude in tinnitus patients. There are changes in event-related potentials when comparing patients with tinnitus and the control group. These changes take place considering the severity of tinnitus, tinnitus site of lesion, and capacity for changes after interventions. The event related potentials can help to determine the neurotransmitter involved in tinnitus generation and evaluate tinnitus treatments.

Resumo Introdução O zumbido é a percepção de um som na ausência de uma fonte sonora. Mudanças nos parâmetros de latência e amplitude nas ondas dos potenciais evocados auditivos relacionados a eventos ou potenciais de longa latência foram citadas em pacientes com zumbido quando comparados a um grupo controle. Objetivo Realizar uma avaliação de evidências científicas que verifiquem a possibilidade de alterações na latência ou amplitude das ondas de potenciais evocados auditivos relacionados a eventos em indivíduos com zumbido. Método Foi feita uma revisão a partir dos bancos de dados científicos SciELO, Lilacs, ISI Web e PubMed. Artigos publicados em inglês, português, francês e espanhol que correlacionavam zumbido com alterações nos potenciais evocados auditivos relacionados a eventos foram incluídos. Resultados Foram localizados 12 artigos, porém apenas oito preencheram os critérios de inclusão. Conclusão A amostra de estudos selecionados demonstra que os potenciais evocados auditivos de longa latência relacionados a eventos entre os pacientes-controle e com zumbido apresentaram algumas alterações na latência e/ou amplitude nos pacientes com zumbido. Há mudanças nos potenciais relacionados a eventos ao comparar pacientes com zumbido e o grupo controle. Essas alterações consideram a gravidade do zumbido, o local da lesão do zumbido e a capacidade de alterações após as intervenções. Os potenciais evocados auditivos relacionados a eventos podem ajudar a determinar o neurotransmissor envolvido na geração do zumbido e avaliar os tratamentos para o zumbido.

Diferencias en procesamiento cerebral visual temprano en niños con trastorno del déficit de atención / Differences in early visual cerebral processing in children with attention deficit / hyperactivity disorders with predominance of no attention

Para evaluar los procesos atencionales a estímulos visuales que no requieren repuesta motora, se llevó a cabo un estudio con potenciales evocados a 17 niños con trastornos del déficit de atención/ hiperactividad (TDAH-I) con predominio inatento y a 15 controles de edades entre 7 y 11 años. Se analizó la latencia y localización de fuentes de los potenciales evocados visuales tempranos P100 y N100 durante la realización de una tarea oddball visual (20% rayas horizontales y 80% verticales) en que las rayas verticales no exigían respuesta motora. Los resultados indican que los niños con TDAH-I procesan la información visual que no requiere respuesta motora con un mayor aumento de la actividad cerebral y mediante la vía temporal ventral mientras que el grupo control lo hace mediante la vía parietal dorsal. Este proceso neurobiológico de procesamiento de la información visual vía temporal ventral de los niños con TDAH-I podría deberse a alteraciones en los procesos emocionales que influyen directamente en el reconocimiento visual o a un déficit en el control de los procesos atencionales por parte de la vía parietal dorsal.

To evaluate attentional processes to visual stimuli that do not require motor response, a study with evoked potentials was carried out on 17 children with attention deficit disorder predominantly inattentive (ADDH-I) and 15 controls between the ages of 7 and 11 years. The latency and localization of sources of the early visual evoked potentials P100 and N100 were analyzed during the performance of a visual oddball task (20% horizontal and 80% vertical lines) where the vertical lines did not require motor response. The results indicate that ADDH-I group process visual information that does not require motor response with a greater increase in brain activity and through the ventral temporal pathway, while the control group does so by means of the dorsal parietal stream. This neurobiological process of visual information processing by ventral temporal pathway of ADDH-I group could be due to alterations in emotional processes that directly influence visual recognition or as consequence of deficit in the control of attentional processes by the dorsal parietal pathway.

Behavioral and neural correlates of emotional development: typically developing infants and infants of depressed and/or anxious mothers / Bases neurais e comportamentais do desenvolvimento emocional: lactentes com desenvolvimento típico e lactentes filhos de mães deprimidas e/ou ansiosas

ABSTRACT Objectives: To describe the main findings of studies of behavioral and neural correlates regarding the development of facial emotion processing during the first year of life in typically developing infants and infants of depressed and/or anxious mothers. Sources: Comprehensive, non-systematic review of the literature on studies about individual differences in facial emotion processing by newborns and infants over the first year of life. Summary of the findings: Maternal stress related to depression and anxiety has been associated to atypical emotional processing and attentional behaviors in the offspring. Recent neurophysiological studies using electroencephalogram and event-related potentials have begun to shed light on the possible mechanisms underlying such behaviors. Conclusions: Infants of depressed and/or anxious mothers have increased risk for several adverse outcomes across the lifespan. Further neurobehavioral investigations and the promotion of clinical and developmental research integration might eventually contribute to refining screening tools, improving treatment, and enabling primary prevention interventions for children at risk.

RESUMO Objetivos: Descrever os principais achados de estudos de correlação entre o comportamento e as bases neurais em relação ao processamento de emoções faciais durante o primeiro ano de vida de lactentes com desenvolvimento típico e lactentes de mães deprimidas e/ou ansiosas. Fontes: Análise abrangente e não sistemática da literatura de estudos sobre diferenças individuais no processamento de emoções faciais de neonatos e lactentes ao longo do primeiro ano de vida. Resumo dos achados: O estresse materno relacionado à depressão e ansiedade tem sido associado a alterações no processamento emocional e na alocação da atenção da prole. Estudos neurofisiológicos recentes utilizando electroencefalograma e potenciais relacionados a eventos começam a esclarecer os possíveis mecanismos inerentes a esses comportamentos. Conclusões: Lactentes filhos de mães deprimidas e/ou ansiosas têm maior risco de problemas de saúde física e mental durante toda vida. O avanço de estudos neurocomportamentais e a promoção de integração entre a pesquisa clínica e de desenvolvimento poderão contribuir para refinar as ferramentas de triagem, melhorar o tratamento e permitir intervenções de prevenção primária para crianças em risco.

Structural and functional neuroimaging findings associated with the use of clozapine in schizophrenia: a systematic review

Objective: Schizophrenia is one of the most severe psychiatric disorders, and its current treatment relies on antipsychotic medications with only partial effectiveness. Clozapine is an atypical antipsychotic with a specific profile of action indicated for treatment-resistant schizophrenia. Neuroimaging studies assessing the effects of clozapine could help shed light on the neural underpinnings of the effects of this drug in the brain. The objective of this study was to review the available literature on the structural and functional neuroimaging findings associated with use of clozapine. Method: We conducted a systematic review of the indexed literature using the PubMed, BIREME, and ISI Web of Knowledge search engines and the following keywords: clozapine, neuroimaging, computed tomography, MRI, functional magnetic resonance, PET, SPECT, and DTI. Results: A total of 23 articles were included in the review. In structural studies, the use of clozapine was associated with volume reductions in the basal ganglia, especially the caudate nucleus, where functional neuroimaging studies also found decreased perfusion. In the frontal lobe, clozapine treatment was associated with increased gray matter volume and reduced perfusion. Conclusion: The results of the studies reviewed suggest that the use of clozapine is associated with distinctive structural and functional neuroimaging findings that are not shared with other antipsychotics. .

Advances in Event-related Potential and Its Forensic Application Value / 法医学杂志

The event-related potential (ERP) is considered as one of the most effective methods to study and analyze objectively human mental activity based on nerve electrophysiology. At present, ERP is not only used in the study of lie detection, but also in the clinical medicine for the cognitive assessment on patients with cerebrovascular disease, dementia or traumatic brain injury and auxiliary diagnosis of mental illness. With the further development of ERP detection technology, it would have a wider application prospect in the field of forensic medicine.

Attentional bias modulation by reappraisal in patients with generalized anxiety disorder: an event-related potential study

Affective states influence subsequent attention allocation. We evaluated emotional negativity bias modulation by reappraisal in patients with generalized anxiety disorder (GAD) relative to normal controls. Event-related potential (ERP) recordings were obtained, and changes in P200 and P300 amplitudes in response to negative or neutral words were noted after decreasing negative emotion or establishing a neutral condition. We found that in GAD patients only, the mean P200 amplitude after negative word presentation was much higher than after the presentation of neutral words. In normal controls, after downregulation of negative emotion, the mean P300 amplitude in response to negative words was much lower than after neutral words, and this was significant in both the left and right regions. In GAD patients, the negative bias remained prominent and was not affected by reappraisal at the early stage. Reappraisal was observed to have a lateralized effect at the late stage.

Lexical-semantic processing in the semantic priming paradigm in aphasic patients / Processamento léxico-semântico no paradigma de priming semântico em pacientes afásicos

There is evidence that the explicit lexical-semantic processing deficits which characterize aphasia may be observed in the absence of implicit semantic impairment. The aim of this article was to critically review the international literature on lexical-semantic processing in aphasia, as tested through the semantic priming paradigm. Specifically, this review focused on aphasia and lexical-semantic processing, the methodological strengths and weaknesses of the semantic paradigms used, and recent evidence from neuroimaging studies on lexical-semantic processing. Furthermore, evidence on dissociations between implicit and explicit lexical-semantic processing reported in the literature will be discussed and interpreted by referring to functional neuroimaging evidence from healthy populations. There is evidence that semantic priming effects can be found both in fluent and in non-fluent aphasias, and that these effects are related to an extensive network which includes the temporal lobe, the pre-frontal cortex, the left frontal gyrus, the left temporal gyrus and the cingulated cortex.

Há evidências de que os déficits de processamento léxico-semântico explícitos que caracterizam a afasia podem ser observados na ausência de déficits semânticos implícitos. O objetivo deste artigo foi analisar criticamente a literatura internacional sobre processamento léxico-semântico na afasia, avaliado por meio do paradigma de priming semântico. Especificamente, esta revisão teve seu foco na afasia e processamento léxico-semântico, pontos fortes e fracos da metodologia dos paradigmas léxico-semânticos usados, e evidências recentes de estudos de neuroimagem sobre o processamento léxico-semântico. Além disso, evidências de dissociações entre processamento léxico-semântico implícito e explícito relatadas na literatura serão discutidas e interpretadas, relacionando-se aos dados de neuroimagem funcional de amostras saudáveis. Há indícios de que os efeitos de priming semântico podem ser encontrados tanto em afasias fluentes como em não fluentes, e que esses efeitos são relacionados a uma extensa rede que inclui o lobo temporal, o córtex pré-frontal, o giro frontal esquerdo, o giro temporal esquerdo e o córtex cingulado.

Increased coherence among striatal regions in the theta range during attentive wakefulness

The striatum, the largest component of the basal ganglia, is usually subdivided into associative, motor and limbic components. However, the electrophysiological interactions between these three subsystems during behavior remain largely unknown. We hypothesized that the striatum might be particularly active during exploratory behavior, which is presumably associated with increased attention. We investigated the modulation of local field potentials (LFPs) in the striatum during attentive wakefulness in freely moving rats. To this end, we implanted microelectrodes into different parts of the striatum of Wistar rats, as well as into the motor, associative and limbic cortices. We then used electromyograms to identify motor activity and analyzed the instantaneous frequency, power spectra and partial directed coherence during exploratory behavior. We observed fine modulation in the theta frequency range of striatal LFPs in 92.5 ± 2.5% of all epochs of exploratory behavior. Concomitantly, the theta power spectrum increased in all striatal channels (P < 0.001), and coherence analysis revealed strong connectivity (coefficients >0.7) between the primary motor cortex and the rostral part of the caudatoputamen nucleus, as well as among all striatal channels (P < 0.001). Conclusively, we observed a pattern of strong theta band activation in the entire striatum during attentive wakefulness, as well as a strong coherence between the motor cortex and the entire striatum. We suggest that this activation reflects the integration of motor, cognitive and limbic systems during attentive wakefulness.

Progress in diagnosis of neurogenic erectile dysfunction / 法医学杂志

Recently, with application of evoked potentials technology in the test of somatic and autonomic nerves, quantitative sensory testing in the detection of small nerve fiber function, and functional magnetic resonance imaging in the detection of senior central function, the detection of neural function has become more accurate. This article reviews the progress and application of diagnostic methods about neurogenic erectile dysfunction in order to provide a reference for forensic diagnosis and research in the future.

Potenciales evocados miogénicos vestibulares: estado del arte / Myogenic vestibular evoked potencials: state of art

El ser humano logra la estabilidad necesaria para poder desempeñar eficientemente las actividades comunes de la vida diaria mediante el sistema vestibular y su constante comunicación con múltiples sistemas, principalmente con el sistema óculo-motor y el sistema propioceptivo. Actualmente y con aumento en su incidencia las consultas por síntomas vestibulares juegan un papel importante en la actividad laboral del otorrinolaringólogo, sumándole a esto la dificultad que existe para corroborar el diagnóstico de una manera objetiva. Se han descrito históricamente múltiples técnicas para evaluar el sistema vestibular en respuesta a un esfuerzo por hacer un mejor diagnóstico y tratamiento de estas lesiones entre las que se encuentra el estudio del Potencial Evocado Miogénico Vestibular (VEMP). El VEMP es una metodología de estudio relativamente nueva, descrita por primera vez como método de evaluación de la función vestibular en la década de los noventa por Colebatch y cols. Es una prueba no invasiva, de bajo costo, fácil y rápido de realizar, transformándose en una herramienta clínica muy útil en la verificación de patologías del laberinto posterior, complementando la exploración otoneurológica tradicional. En el presente trabajo de revisión se exponen generalidades, definición, historia, fundamento fisiológico, métodos y aplicaciones clínicas de los VEMP...

The human being attains the stability required to efficiently perform common activities of daily living by the vestibular system and includes communication with multiple systems, mainly with the oculo-motor system and the proprioceptive system. Currently, and with increased incidence of vestibular symptoms consultations play an important role in the work activity of the otolaryngologist, adding to that the difficulty to confirm the diagnosis in an objective manner. Historically have been reported multiple techniques to evaluate the vestibular system in response to an effort to better diagnosis and treatment of these pathologies among which is the study of Vestibular Evoked Myogenic Potentials (VEMP). The VEMP is a relatively new research methodology, first described as a method of evaluating vestibular function in the early 90’s by Colebatch et al. It is a noninvasive test, low cost, easy and quick to perform, making it a useful clinical tool in the verification of pathologies of the posterior labyrinth, complementing the traditional neuro-otological examination. The present review presents an overview, definition, history, physiological basis, methods and clinical applications of VEMP...

Implante coclear: correlação da recuperação neural, privação auditiva e etiologia / Cochlear implant: correlation of nerve function recovery, auditory deprivation and etiology

TEMA: a Função de Recuperação do Nervo Auditivo (REC) pode ser extraída do potencial de ação das fibras neurais - ECAP (Eletrically Evoked Compound Action Potential). O ECAP pode ser influenciado pela estimulação recebida pelo nervo e pela etiologia de uma perda auditiva e, consequentemente, afetar a REC. OBJETIVO: verificar se há correlação entre REC e os fatores: etiologia, tempo de surdez e tempo de uso do AASI antes do Implante Coclear (IC). MÉTODO: estudo retrospectivo transversal. Foram coletados dados sobre etiologia, tempo de surdez, tempo de uso do Aparelho de Amplificação Sonora Individual (AASI) e REC de 50 indivíduos, 26 crianças e 24 adultos, submetidos à cirurgia de IC e usuários do dispositivo multicanal Nucleus®24. As medidas da função de recuperação do nervo auditivo foram calculadas e os pacientes foram divididos em grupos (GI: recuperação rápida, GII: recuperação intermediária e GIII: recuperação lenta) para posterior análise de relação com os demais dados coletados. RESULTADOS: a análise dos dados não mostrou correlação estatisticamente significante entre a recuperação e os aspectos pré-cirúrgicos estudados. Entretanto, foi possível observar maior concentração de ambos, crianças e adultos, nas REC intermediárias. GI não agrupou indivíduos com surdez de etiologias infecciosas, tais como a meningite, rubéola e citomegalovírus. A média de REC apresentou-se mais lenta para as etiologias infecciosas, tanto para o grupo de crianças, como para o grupo de adultos. CONCLUSÃO: não houve correlação estatisticamente significante entre função de recuperação do nervo auditivo e os fatores: etiologia, tempo de surdez e tempo de uso do AASI antes do IC.

BACKGROUND: the Auditory Nerve Recovery Function (REC) may be extracted from the Electrically Evoked Compound Action Potential (ECAP). ECAP may be influenced by the stimulation received (or the deprivation of stimulation) and by the etiology of the hearing loss, consequently it might affect the REC. AIM: to verify whether there is a correlation between the REC and each of the following factors: etiology, time of auditory deprivation and time of hearing aid use before cochlear implantation (CI). METHOD: retrospective study. Data regarding etiology, time of auditory deprivation, time of hearing aid use before cochlear implantation were collected in children and adults who received a Nucleus®24. All patients who presented neural response at surgery and whose REC was assessed intraoperatively were included in this study. Fifty patients were selected, 26 children and 24 adults. Patients were divided according to the REC classification into three groups (GI: fast recovery; GII: intermediate recovery and GIII: slow recovery) to allow correlation analysis. RESULTS: data analysis did not show any statistically significant correlation between the recovery function and the pre-implant studied characteristics. Nevertheless, it was observed that there was a greater concentration of both, children and adults, in the intermediate recovery function values. GI did not present individuals with infectious etiologies, such as meningitis, rubella and cytomegalovirus. REC average scores were slower in infectious etiologies for both children and adults. CONCLUSION: there was no statistically significant correlation between the recovery function and factors such as etiology, time of auditory deprivation and time of hearing aid use prior to CI.

Progress on neuropsychology and event-related potentials in patients with brain trauma / 法医学杂志

With the development of information technology, as one of the research frontiers in neurophysiology, event-related potentials (ERP) is concerned increasingly by international scholars, which provides a feasible and objective method for exploring cognitive function. There are many advances in neuropsychology due to new assessment tool for the last years. The basic theories in the field of ERP and neuropsychology were reviewed in this article. The research and development in evaluating cognitive function of patients with syndrome after brain trauma were focused in this review, and the perspectives for the future research of ERP was also explored.

Características neuropsicológicas del niño preescolar con hipotiroidismo congénito en la Provincia de Cienfuegos / Neuropsychological characteristic of preschooler children’s with congenital hypothyroidism in Provincia de Cienfuegos

El hipotiroidismo congénito es la causa más frecuente de retraso mental previsible. El diagnóstico clínico en las primeras etapas de la vida es muy impreciso, de ahí que se hayan puesto en marcha programas de diagnóstico y tratamiento precoz cuyo objetivo fundamental es un desarrollo neurocognitivo y su nivel optimización. Método y objetivos: Con el objetivo de evaluar el perfil neurocognitivo en niños hipotiroideos en edad preescolar se realizó un estudio descriptivo prospectivo que incluyó a los pacientes en edades entre 4 a 6 años con seguimiento en consulta de hipotiroidismo congénito del Hospital Pediátrico “Paquito González Cueto” de Cienfuegos. Solo existían 6 niños a los cuales se les aplicó la batería neuropsicológica Luria Inicial, rendimiento intelectual, escala de comportamiento y potenciales evocados. Resultados: Se constató que estos pacientes presentan limitaciones en el sistema óptico- espacial y en el sistema de control inhibitorio. El primero afecta el desarrollo de la orientación espacial del acto motor y la percepción visual con detalles y el otro sistema afecta el control atencional en la edad y conlleva a dificultades para seguir instrucciones verbales. Recomendación: El seguimiento y la vigilancia del neurodesarrollo permiten ir explicando las alteraciones sistemáticas que se presentan en estos niños y hace posible una intervención temprana a favor del posterior proceso de escolarización.

The congenital hipotiroidismo is the most frequent cause of foreseeable mental delay. The clinical diagnosis in the first stages of the life is very vague, for that reason diagnostic programs and precocious treatment have started up whose main target is a neurocognitivo development and its level optimization. Method and objectives: With the aim of evaluating the neurocognitivo profile in hypothyroid children in pre-school age a prospective descriptive study was realised that it included to the patients in ages between 4 to 6 years with pursuit in consultation of congenital hipotiroidismo of the Paediatric Hospital “Paquito González Fortified height” of Cienfuegos. 6 children only existed to who he was applied the neuropsicológica battery Initial Luria, intellectual yield, evoked scale of behavior and potentials to them. Results: It was stated that these patients present/display limitations in the space optical system and in the inhibiting control system. First it affects the development of the spatial orientation of the motor act and the visual perception with details and the other system affects the attention control in the age and entails to difficulties to follow instructions verbal. Recommendation: The pursuit and the monitoring of neurodesarrollo allow to be explaining the systematic alterations that appear in these children and makes an early intervention in favor of the later process possible of schooling.

The progress in the study of visual field in spatial attention by event related potentials / 法医学杂志

Event-related potentials (ERP) is a good temporal resolution method to study the mechanism of visual field in brain. With the development of technique of high-density recording and brain imaging, the ERP is widely used in the location of the brain function. This article reviews the methods, results and primary conclusions in the field, and suggests several perspectives for the future research and application of ERP in the forensic science.

Voluntary modulations of attention in a semantic auditory-visual matching Task: an ERP study

The present study explores the neural correlates of voluntary modulations of attention in an auditory-visual matching task. Visual stimuli (a female or a male face) were preceded in close temporal proximity by auditory stimuli consisting of the Spanish word for "man" and "woman" ("hombre" or "mujer"). In 80 percent of the trials the gender of the two stimuli coincided. Participants were asked to mentally count the specific instances in which a female face appeared after hearing the word "man" (10 percent of the trials). Our results show attention-related amplitude modulation of the early visual ERP components NI and anterior P2, but also amplitude modulations of (i) the N270 potential usually associated with conflict detection, (ii) a P300 wave related to infrequency, and (iii) an N400 potential related to semantic incongruence. The elicitation of these latter components varied according to task manipulations, evidencing the role of voluntary allocation of attention in fine-tuning cognitive processing, which includes basic processes like detection of infrequency or semantic incongruity often considered to be volition-independent.

Mismatch negativity: análise dos efeitos da hipotermia e do treinamento auditivo a partir de um modelo de estudo experimental / Mismatch negativity: analysis of temperature and auditory training effects from an experimental study model

INTRODUÇÃO: Lesões cerebrais isquêmicas ocorrem em índices bastante significativos, podendo levar a alterações cognitivas de graus variados, cujas repercussões clínicas podem ser de extrema gravidade para os pacientes acometidos. Para avaliar as conseqüências destas lesões nos aspectos funcionais, pode-se utilizar um dos componentes dos potenciais evocados auditivos relacionados a eventos, o Mismatch Negativity (MMN). OBJETIVOS: verificar se o MMN é capaz de detectar mudanças eletrofisiológicas em gerbils submetidos à isquemia cerebral e a hipotermia; verificar se o treinamento auditivo pode gerar mudanças eletrofisiológicas detectáveis pelo MMN, e comparar as latências do potencial com as células sobreviventes do hipocampo de gerbils submetidos à isquemia e a hipotermia. MÉTODOS: Estudo 1: 44 gerbils (Meriones Unguiculatus) adultos foram anestesiados com halotano e submetidos à isquemia cerebral através da oclusão bilateral das carótidas por sete minutos, e à captação do MMN. Os animais foram divididos nos grupos SHAM, HIPO, NORMO e HIPER, de acordo com a temperatura a que foram submetidos. Estudo 2: 28 gerbils foram submetidos a uma sessão de treinamento auditivo com duração de 300 segundos em caixa de esquiva com gerador de eletrochoque, e ao registro do MMN. Estudo 3: foi captado o MMN de 27 gerbils e, após terem sido sacrificados, foi realizada a quantificação de células sobreviventes da região CA1 do hipocampo através de cortes histológicos. RESULTADOS: Estudo 1: houve 100% de presença do MMN no grupo HIPO, não houve diferença estatisticamente significante entre os grupos SHAM e HIPO. Estudo 2: não houve diferença estatisticamente significante entre as latências do MMN antes e depois do treinamento auditivo. Estudo 3: observou-se maior número de células sobreviventes no hipocampo nos animais do grupo HIPO, e foi detectada baixa correlação entre o número de células sobreviventes e a latência do MMN. CONCLUSÕES: o MMN detectou as mudanças...

INTRODUCTION: Significant ischemic cerebral lesions may result in cognitive disorders of varying degrees, with clinical repercussions that could be extremely severe for the affected patients. In order to evaluate the consequences of such lesions upon functional aspects, one of the components of event-related auditory evoked potentials, the Mismatch Negativity (MMN), may be used. AIM: to verify whether the MMN is able to identify electrophysiological changes in gerbils submitted to cerebral ischemia and hypothermia; to verify if auditory training may generate electrophysiological changes detectable by MMN, and to compare the potential's latencies with the surviving cells of the hippocampus of gerbils submitted to cerebral ischemia and hypothermia. METHODS: Study 1: 44 adult gerbils (Meriones Unguiculatus) were sedated with halothane and underwent cerebral ischemia through bilateral occlusion of the carotids for seven minutes, and the MMN was registered. Animals were divided in four groups, SHAM, HIPO, NORMO and HIPER, according to the temperature they were exposed. Study 2: 28 gerbils underwent a session of auditory training of 300 seconds in a passive shuttle box with an electroshock generator, and the MMN was registered. Study 3: the MMN of 27 gerbils were registered and after their scarifice, the amount of surviving cells in the CA1 region of the hippocampus was quantified through histological cuts. RESULTS: Study 1: the MMN was 100% present in the HIPO group, there was no significant statistical difference between groups SHAM and HIPO. Study 2: there was no significant statistical difference between the MMN latencies before and after the auditory training. Study 3: a greater number of surviving cells was observed in the hippocampus of animals from group HIPO, and a low correlation between the number of surviving cells and the MMN latency was detected. CONCLUSIONS: MMN detected electrophysiological changes...